Containerised handling of bulk materials and apparatus therefor

ABSTRACT

A freight container ( 10 ) has a base ( 20 ) or a portion thereof that can be opened to discharge its contents. This container ( 10 ) has a top which can be opened in similar manner as the base. Another container having at least one compartment, each compartment having a lower section with a reducing cross-sectional area and a pivotably operable closure assembly, with several such closure assemblies being linked together by means of bars. Such a container is used to contain raw building materials for stockpiling of these materials at a container port. It is also used to supply materials to a concrete production plant whee pollution control containers are provided below the supply container and above the scaling and mixing stations to reduce particulate pollution. A pair of slewing apparatuses is also provided to engage both ends of a container and turn the container over about its longitudinal axis, thereby emptying its contents.

FIELD OF THE INVENTION

This invention relates to containerised handling of bulk materials, forinstance raw building materials. It also relates to stockpiling andbatching of such materials using containers in general.

BACKGROUND OF THE INVENTION

Containers can be used to carry bulk materials, for instance rawbuilding materials. However, one problem with this is that suchmaterials are not always easy to unload. The containers tend to betipped up from one end, so that the materials fall out of the other.However, this is not just a simple matter of tipping by a few degrees.Some materials require a tipping angle of over 45° to be fully unloaded.This requires tipping equipment and space and moreover can cause a lotof dust and mess.

An alternative to using a normal box container is to use a tank or silocontainer (with the tank in a container frame). The materials there areemptied through valves at the base. Whilst this may work for drymaterials, it tends not to work for damp ones; the valves clog up.

The transportation of bulk materials is well exemplified by concrete.Concrete is a common construction materials and is a composite ofcement, sand, gravel and water. The strength of cured concrete dependson the proportions of each component. Additives may be added to improvethe fluid properties of the concrete during mixing and/or casting;others may be added to improve the hardness of the concrete aftercuring; colour pigments can also be added to give the concrete adistinct colour for a specific application, such as to differentiate thefloor areas at a factory.

These raw materials are normally supplied in bulk by separate suppliers.For example, cement is manufactured only at a specialised plant, wherelimestone and large electric power are readily available and only at thelocations approved by the environmental authorities. Similarly, gravelsare produced at the quarries and the industry is also controlled by theenvironmental authorities. Sand may be dredged out from the sea or riverbed. These raw materials are then transported to a batching plant. Thismay be at a construction site, but in many cases, there is no landavailable for an on site concrete batching plant or there may be otherreasons why it is not feasible. In such cases, the raw materials arebatched at a remote batching plant and transported to site by concretemixers. This remote batching plant may have to occupy a large piece ofland to stockpile the raw materials. In land-scarce countries, such asin Singapore, efficient use of land is a concern.

In many places, all the raw building materials are imported from thesurrounding regions; gravel may come from one place with sand and cementcoming from again different places. Typically, gravel and sand aretransported by barges, while cement by specialised ship. At the landingpoint, these materials are stockpiled and then transferred to thebatching plants or construction sites.

These batching plants and landing points are normally open facilitiesand the transfer of huge amounts of materials generates a lot of dustinto the air. Abatement of dust pollution is therefore important.

Tipping of a container mounted on a truck tends to cause a lot of dust.Also tipping of a container suspended on a crane is not a safe practice.Shipping of wet sand and gravels in silo or tank containers does notwork.

These problems necessitate a search for simpler and economical means ofshipping and transfer of bulk materials and yet reducing pollution fromthe present levels.

SUMMARY OF THE INVENTION

This invention provides novel containers and, inter alia, an apparatusand system for containerised handling of raw building materials. Thesecontainers are handled at a container port and are stockpiled at thestacking yard. Sand and gravel (aggregate) can also be batched intomixer containers for stockpiling.

According to a first aspect of the present invention, there is provideda container for transferring bulk materials, being shaped, dimensionedin length and width and operable as a standard freight container andhaving a base, at least a portion of which is openable for dischargingcontents of the container therethrough.

The base or a portion thereof can be slidable, pivotable, hinged,swingable, displaced vertically, etc.

Preferably, the container has at least one compartment, the or eachcompartment having at least one lower section of reducingcross-sectional area, each leading to an opening, and a closure assemblyfor the or at least one opening, for releasing or retaining thecompartment's contents. Moreover, the or at least one closure assemblyis preferably pivoted.

According to a second aspect of the present invention, there is providedslewing apparatus for turning a container comprising:

-   -   a supporting portion;    -   a rotatable, container holding portion; and    -   means for rotating said container holding portion on said        supporting portion; wherein    -   said container holding portion comprises:    -   a base portion for supporting and fastening to the lower part of        a container; and    -   arm means extensible in a first direction and having fastening        means with an extent in at least a second plane, orthogonal to        said first direction, for fastening to the upper part of a        container;    -   wherein said fastening means is rotatable between a first        position where it cannot fasten said container, whilst the        container is supported and fastened to said base portion, and a        second position, where it can fasten said container, whilst the        container is supported and fastened to said base portion.

Preferably, when said fastening means is in said first position, acontainer can be placed for fastening to said base portion or removedtherefrom, and, when said fastening means is in said second position,the fastening means obstructs a container from being placed forfastening to said base portion or removed therefrom.

Advantageously, the base portion may be arranged to support a containerfrom below and said fastening means arranged to fasten to a containerfrom above.

Preferably two such apparatus are used together, one for each end of acontainer.

A pollution control enclosure for use with the slewing apparatus is alsoprovided.

According to another aspect of the invention, there is provided a systemfor producing a mixture of components, comprising:

-   -   at least one stocking section having a stocking chamber for a        component; and    -   a scaling section for determining and delivering a scaled amount        of each component;        and operable such that a container may be stacked on top of said        stocking section for replenishing said component therein.

This system for producing a mixture of components, may further comprisea section for holding or blending the scaled components beforedischarging the mixture.

This could be by using a container as above or the slewing apparatus asabove.

Preferably the system includes a pollution control section for usebetween at least said container and said stocking section for abatingparticulate pollution as material is discharged into the stockingsection.

The stocking section, scaling section, mixing section and the one ormore pollution control sections ideally are shaped, dimensioned,transportable and stackable as a standard freight container.

This system is advantageous for producing concrete.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be further described by way of non-limitiveexamples with reference to the accompanying drawings, in which:

FIGS. 1 a-1 c show containers having a sliding base plate in one or twoparts, according to one aspect of the invention;

FIGS. 2 a-2 e show containers having a hinged base plate in one or twoparts, according to embodiments of the invention;

FIGS. 3 a-3 b show a compartmentalised container, being anotherembodiment of the invention;

FIGS. 4 a-4 b show a container with both a base and top that can beopened;

FIGS. 5 a-5 e show details of containers according to furtherembodiments;

FIGS. 6 a-6 f show details of containers according to yet moreembodiments;

FIGS. 7 a-7 c show a slewing apparatus for a container according toanother aspect of the invention;

FIGS. 8 a-8 g show a system for containerised handling of raw buildingmaterials at a concrete production plant, according to yet anotheraspect of the invention;

FIGS. 9 a-9 c show a pollution control enclosure for a slewingapparatus;

FIG. 10 shows another system for containerised handling of raw materialsat a concrete production plant;

FIGS. 11 a-11 d show interfacial seals between stacked-up containers,according to again another aspect of the invention;

FIGS. 12 a-12 c show covers for preventing waste of raw materialsaccording to yet again another aspect of the invention; and

FIG. 13 shows a system for containerised handling of raw buildingmaterials at a port.

DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

FIG. 1 shows a container 10 with a single sliding base plate 20. Thiscontainer 10 has the same or similar external length and widthdimensions and corner castings as a regular freight container already inuse, such as that of an ISO-type or SeaLand-type container. The heightcan be non-standard, although standard heights may be preferred.However, the base is different, allowing the base plate 20 to slideopen. In this manner materials within the container can fall out of thebottom. The base frame of the container has support bars 30 supportingthe base plate when closed and keeping it rigid under the weight of theraw materials. These support bars 30 are preferably pointed or curved atthe top to prevent material settling on them when it falls.

Additionally, around the edges of the base plate 20, there are seals 15to prevent material in the container getting around the ends and sidesof the base plate 20 and escaping or clogging up the sliding action.

The base plate 20 need not be a single piece. It can be made of twopieces 20′, 20″ as shown in FIGS. 1 b and 1 c, preferably with anoverlapping edge 21. This has the advantage that the opening of the basecan be carried out from either or both sides, if and when spaceconstraints require it. A single container can have two or moreindependently movable or immobile base plates along its length and/orits width. There may be containers where the split is not central and/orwhere one side is immobile.

In another embodiment of this invention, FIG. 2 a shows a hinged baseplate 22 instead of a sliding one. Preferably, this hinged base platecomprises two pieces 22′, 22″ as shown in FIG. 2 b, with the pivot axesalong the base struts of the container frame and the overlapping edgessubstantially mid-way in between. For a long container, such as atwenty-footer, it is possible to have the hinged base plates across thecontainer in several sections 24 so as to ensure rigidity of the base(see FIG. 2 c). It is also possible that a strut 31 be provided alongthe centre(s) of the base frame(s) of the container, in either the longor the short section. In this way, the moving edges of the base platesmay abut the centre strut 31 offering more secure locking and releasingmechanisms and greater strength. The hinges may be located at struts 31instead of the edge struts of the container (FIGS. 2 d and 2 e).

A further embodiment compartmentalises the container 10′ to handlevarious raw building materials at the same time (FIGS. 3 a and 3 b). Inthis way, for example, sand and/or gravel (aggregate) can be batchedinto different compartments of a container. With this provision, it ispossible to supply a container of sand and aggregate to a blendingstation to produce concrete with different structural strengths (havingdifferent compositions of sand, aggregate, cement and water). Withprescaling of each batch of material, it is also possible to do awaywith the scaling station at a typical cement batching plant. Threecompartments are shown but there may be any other number withcompartments separated along the length and/or width of the container.

A further embodiment is shown in FIGS. 4 a and 4 b, which has a top thatcan be similarly opened. This feature allows easy loading whilstafterwards covering its contents, especially sand, and ensures that themoisture content is maintained during shipping or stockpiling.

The sliding action of the base plate (or sections of it) can be achievedby means of built-in hydraulic cylinders and a (remote) hydraulic powerunit. This method is preferred for the large power that it can deliver,yet the cylinders are compact enough for installation below the baseplate. With some compact control units, installed at an edge of thecontainer for example, an operator can easily operate the cylinders toslide open the base plate. By operating different control units,different sections of the base plate can be opened. The cylinders andcontrol units may be connected at least in some parts by flexible hosesthat are in common use. The flexible hoses allow relative movementbetween the cylinders and control units thereby making the opening ofthe base possible. The control unit may be integrated with the powerunit.

In the same manner, hydraulic cylinders, for example, may be used torelease the catches of the locks for the hinged base plate or sectionsof it. Hydraulic power is preferred, due to its huge power, compactcylinders and control units, and flexible power lines. Additionalhydraulic cylinders may be provided to enable closing of the hinged baseplate. This is particularly useful when access to close the hinged baseis not possible for safety reasons, for example.

The movable base plates are also provided with handles, which allow themto be pulled from outside, for example by a hook on a chain, a forklift.Other means, especially rotary means, such as a motor connected to areduction gear set driving a rack and pinion assembly; or a winch andcable mechanism may be used.

It is also possible that the actuators (both linear and rotary) foroperating the base plate (or sections of) of container 10, 10″ aremounted in the structure on which container 10, 10″ sits. In this case aprojection at the moving end of the actuator engages with a catch on thelower side of base plate 20 (or sections 20″ of it). The advantage ofthis feature is that only one set of operable mechanism is required ateach material discharge point.

FIGS. 5 a and 5 b show yet another embodiment of a container fordischarging its content through an openable base, the details of whichare shown in FIG. 5 c. The container 10′″ is illustrated with threefunnel portions in its lower part, which are sealed by operable pivotingbase plates 32. Pulling a pivoting base plate 32 to one side allows thematerial in the container to fall out through the end of the funnel. Inthis embodiment, the three pivoting base plates 32 are interconnected,such that pulling one aside, pulls all three. However, in some otherembodiments, especially where the container is compartmentalised, thiswould not be so. Of course there do not have to be three of thesefunnels and opening portions. There could be any number, from oneupwards.

As can be seen from FIGS. 5 a to 5 c, each pivoting base plate 32, ismade up mainly of two vertical end hinge plates 32 a, one at each end,and an interconnecting base portion. The base portion has, as its upperpart, an arcuate closure plate 32 b. The centre of the closure plate 32b is its lowest part. Below this is a triangular support structure 32 c.Two of the apices of the support structure 32 c are common to the endsof the arcuate closure plate 32 b. The third apex is below the centre ofthe closure plate 32 b, this being its lowest point.

The main part of the closure plate 32 b closes off the base of thefunnel portion 33, thereby preventing material from passing out. Theends of the closure plate, however, extend beyond the edges of thefunnel to ensure complete closure. Seals 38 on each side preventmaterials slipping between the end of the funnel and the closure plate.

The vertical end hinge plates 32 a are pivoted to the outside of thefunnel 33, allowing them to swing to either side. In so swinging, theinterconnecting closure plate also swings to one side, thereby openingthe funnel. The arcuate shape of the closure plate is centred on thepivot axis of the end hinge plates 32 a to allow it to swing past theedges of the funnel without allowing any material to get between them.However, this is not essential.

The end plates are shown as solid, but could mainly consist of barsaround its edges instead. They are shown as hinged to the funnel 33, butcould be hinged to the container walls or other struts. Funnels 33 areshown as narrowing in two orthogonal directions, but do not need to.They need only narrow in the direction of swing of the closure plate. Inthe other orthogonal direction they only need to allow the end plates topivot outside them.

The closure plates are shown as being perforated. Perforations 32 dallow water collected in container 10′″ to drain out and maintain themoisture of the material. Below the perforated closure plate 32 b is afilter material 32 e, such as a sponge, for example. The filter material32 e allows water to pass through but keeps the material inside thecontainer. Inside support structure 32 c is a sloping plate 37. Plate 37keeps filter material 32 e in place and directs water to port 32 f. FIG.5 b shows two sloping plates 37, 37′ but may, for example, have only onesloping in one direction. A hose or pipe may be connected to port 32 fto direct water beyond the container boundary, thus preventing waterfrom the upper containers dripping into the lower containers.

The opening mechanism will now be described. A hook 34 is pivoted onsupport structure 32 c at pivot 34 a. Pulling the hook pulls thepivoting base plate 32. In order to open all the compartments ofcontainer 10′″ at the same time, link bars 36 are provided between theindividual pivoting base plates 32. These are pivoted on the supportstructure 32 c at pivot points 36 a. The pivot points 36 a and 34 a maywell be common, if required. In addition, springs 36 b, 36 b′ areprovided between the funnels and hooks 34 and/or link bars 36 to returnthe pivoting base plates 32 to their closed positions.

A remote activation bar 35 below the container 10′″ may be used toengage hook 34 when container 10′″ is lowered to its discharge position.Its height is set to push the hook upwards during lowering, to pull thebase plates 32 open, thereby opening the base of container 10′″ andallowing its content to fall out. The height of activation bar 35 isadjustable. This allows for easy control on the opening of bases 32.Once the container 10′″ is emptied and the container is hoisted up,bases 32 return to their closed position by gravity (and springs orother biasing means).

In order to reduce the load on the base 32, the area of the openablebase should be kept low, whilst allowing the contents to be dischargedin a controlled manner and within a reasonable rate. This also meansthat the base 32 should be of a reasonable size and mass.

An alternative mechanism for opening the pivoted base plate 32 is toreplace the remote activation bar 35 with an actuator 35 a, such as apneumatic or hydraulic cylinder as shown in FIG. 5 d. Once thereplenishing container 10″ is placed at the material discharge point(which can be a container), actuator 35 a is extended and engaged withthe catch fixedly mounted on base plate 32, thereby turning it about itspivot and opening the base of the compartment of container 10″. Linkbars 36′ may be used to link the base plates 32 of two or morecompartments.

A variation of the opening mechanism is to mount the actuator 35 a′directly to container 10″ as shown in FIG. 5 e. This may be useful suchas when the lifting facility has limited headroom.

FIGS. 6 a and 6 b show yet another embodiment of a container 10″ fordischarging its contents through an openable base. As illustrated inthese figures, the base of the container comprises a plurality of pairedinclined plates 25 extending across the base of the container and spacedapart from each other. These plates 25 slope at an angle of between 20and 60° to the vertical. They are joined at the upper edges, formingtriangular shaped sections 26 across the width of the container. Thespaces between each pair of these sections 26 form discharge chutes 27through which the contents are discharged. At each end of the containeris another inclined plate 25 whose upper edge is joined to the end walland the lower edge joined to the base. These inclined plates 25,together with the nearest inclined plates of adjacent sections 26 alsoform discharge chutes 27.

The discharge chutes 27 are kept closed by means of triangular-shapedcovers 28 extending across the width of the container. These covers 28are substantially symmetrical about the vertical. This profile ensuresthat the flow of the content creates equal opposing dynamic lateralforces on both sides of a cover, and this ensures that each cover 28 islocated at the centre of the discharge space 27. The symmetrical sidesof covers 28 also ensure that the lateral components of the weight ofthe content on the cover are balanced whilst the vertical componentinduces self-closing of the covers.

FIG. 6 a shows actuator means 29 installed vertically in the spacedirectly below covers 28 and part of the container. These actuators areoperable to extend vertically for pushing or lifting the covers fromtheir closed position and allowing the contents to discharge through thespace between the covers 28 and the inclined plates 25. These actuatorsare connected to direction control valves by pipes conveying thecompressed fluid, either pneumatic or hydraulic. These controls (notshown in the figure) are conveniently installed in the void space belowthe triangular sections 26 and are accessible from a side of thecontainer. Of course, a plurality of the actuators may be linkedtogether and are operable as a group from a control valve. Additionalset(s) of control valves may be provided at opposite sides of thecontainer for the ease of operation.

To prevent wear and tear on the actuators 29 due to the flow of thematerials discharging from the base of the container, there may beprovided a sacrificial cover 29 a around each actuator. This sacrificialcover 29 a can then be replaced at regular intervals as and whennecessary.

FIG. 6 b illustrates the opening of covers 28 in another embodiment whenthe container is lowered on top of a pollution control container 120(shown in FIG. 8 a or 8 b) for discharging its content therethrough. Inthis embodiment, the actuators 29 do not form part of the container butare located as part of or in addition to the pollution control container120, at a material landing or discharge site. Similarly, the controlmechanisms, such as the pneumatic or hydraulic lines and direction flowcontrol valves are also located with the pollution control container120. This helps to reduce the hardware cost of a container of thisembodiment.

Each actuator in FIG. 6 a or 6 b need not be controlled by a separatecontrol mechanism. They can be linked up in parallel, or even in seriesdepending on the actuators used. Of course, the number of actuators orcontrol mechanisms is not a limitation.

FIG. 6 c illustrates another embodiment and the opening of covers 28with the use of fixed activation bars 29 b installed on the pollutioncontrol container 120, instead of an extensible piston means. Thus theact of lowering the container causes the discharge chutes to be opened.

It is noted that installation of these actuators 29 or activation bars29 b are not confined to the pollution control container 120. They couldbe similarly installed elsewhere, such as on a stock container 104, 110or discharge container 102 (as described later in FIG. 8) depending onthe apparatus adopted for each material handling facility.

FIGS. 6 d and 6 e illustrate yet another method of opening covers 28. Asshown in FIG. 6 d, the top edge of cover 28 has two points spaced apartfrom each other, to each of which is attached an end of a rope 28 a. Theother end of each rope is attached to a cross bar 28 b moveablypositioned across the container near the top. The ends of the cross bar28 b have hooks for engaging the top edge of the container. Engaging thecross bars 28 b, for example using additional hooks from the liftingequipment, and hoisting them up a distance pulls the covers 28 up,thereby opening the chutes to discharge the contents of the container. Apair of sliding guides adjacent the upper edge of the container, orother suitable means for allowing the repositioning of each cross bar 28b after they have been lifted, may be provided instead of hooks.

To prevent wear and tear on the ropes, a sacrificial pipe 28 c isprovided around each rope 28 c. At the base of pipe 28 c is attached aV-shaped plate 28 d. This V-shaped plate 28 d fits onto the upper edgeof cover 28 and provides additional support for the pipe or rope.

The cross bars 28 b are linked to each other by means of a pair oflengthwise bars 28 e so that hoisting the lengthwise bars 28 e at eithertwo or four points is sufficient to pull all the covers 28 up and openthe discharge chutes 27. Alternatively, a single bar 28 e is provided atthe centre of 28 b linking all the cross bars 28 b together and two hookengaging points on 28 e may then be used for opening all of the covers28 simultaneously.

Variations of this embodiment are also possible. A variation is toprovide covers with other cross-sections, for example, a partialcylindrical section. Another variation, as shown in FIG. 6 f, is toprovide a slanting rope with each end attached to each of the twoattachment points on cover 28 with the centre part of the rope goingover a single cross bar 28 e. In order to help locate cross bar 28 e atthe centre of the container, at least two cross-bars 28 b are providednear the two ends of the container. Sacrificial pipes may be providedhere too around the ropes for reducing direct wear and tear of the ropesand indirectly the maintenance cost. Another variation is to do awaywith the rope but to use the sacrificial pipe or some other link, forexample, a cable or chain, for lifting the covers 28.

Another aspect of the invention is shown in FIGS. 7 a-7 c. In thisaspect, open top or opened top containers are discharged by turning themupside down using a slewing apparatus 40.

A support structure 47 rotatably mounts a slewing structure 42, using aslew ring 41. An outer ring 41 a of slew ring 41 is fixedly mounted onthe slewing structure 42. An inner ring 41 b of the slew ring 41 ismounted on the support structure. A motor, gearbox and pinion assembly48 is mounted on support structure 47 for turning slew ring 41 a.Depending on the turning torque required, additional drive assembly maybe provided.

Slewing structure 42 has a base portion with twistlocks 45 forsupporting and affixing to the lower corner castings of a standardfreight container. It also has two vertically operable hydraulicactuators 43 at its sides for adjusting the heights of two verticallymovable clamping supports 44. The tops of these supports 44 havetwistlocks 46 for affixing to the upper corner castings of a standardfreight container, for clamping it against the base portion. The uppertwistlocks 46 are on arms which can rotate about vertical axes in thevertical portions of the clamping supports 44. They can be turnedthrough 90° to become clear of the container to be handled. This allowsthe container to be loaded vertically onto the slewing structure 42. Theangle of rotation could be slightly less or could be more, even allowing360°. The axis could even be horizontal to allow the arms to pivot in avertical plane.

The clamping supports 44 and upper twist locks 46 can also oralternatively pivot about a horizontal axis between first and secondpositions. In the first position support 44 is in a horizontal positionwith twistlock 46 directed downwards. Support 44 can also swing upwardto its second position and become clear of the way for a supplycontainer to be lowered vertically. Once the lower twist locks 45 haveengaged with the lower corner castings of the container, the supports 44and upper twist locks 46 are moved back to their first positions. Theyare then lowered by retracting actuators 43 before engaging with theupper corner castings. These operations can also be simultaneous orordered in other ways.

When a container is locked onto the slewing structure 42, the slew ring41 is rotated to turn the slewing structure 42 and container throughsubstantially 180° to empty out its contents. It can then return to itsupright position back through the 180° it came or through the remaining180°.

Support structure 47 can be mounted on the ground, on a trailer, on aforklift or on other suitable structures or vehicles.

As full containers can be very heavy, the preferred embodiment has twosuch slewing apparatuses 40, one for each end. A preferred arrangementis shown in FIG. 7 c, where two slewing assemblies 40 are mounted on aguide rail 49 to allow for variations in lengths of containers. Althoughboth are shown as being at adjustable positions, only one needs to beadjustable or on the rail.

FIG. 8 a illustrates a containerised batching plant where variouscomponents are batched together in bulk, for instance for concrete. Eachtype of raw material used has its own feeding stack 100, which comprisesan assembly of containers stacked on top of each other. The bottom,discharge container 102 has an outlet chute 50 through which thematerial is transferred by a feeder, for example a conveyor, to ascaling station 60 before it is blended with other components in astation 70. From there it may be loaded into a mobile mixer or othercontainer. Station 70 may be a mixing device and/or a stock holdingdevice.

Depending on the amount of stock of material required, there is at leastone stock container 104, 110 stacked above the discharge container 102.For purposes of automation, a minimum material level sensor 103 isprovided near the base of the discharge container. Two stock containers104, 110 are shown. The three containers hold a stock of the relevantmaterial. Near the top of the stock container(s), is a material levelsensor 105 for detecting the upper limit of the material stock.

FIG. 8 b shows a container 10 full of relevant materials on the top ofthe stack 100. It empties downwards into a pollution control container120 which itself empties into the top-most stock container 104. Aretractable vibrator may be connected to the outside of the supplycontainer 10. This is used as and when necessary, for example when thesand is wet and it is difficult for it to begin to fall by gravity or tominimise the amount of wet sand remaining on the inside surfaces of thesupply container.

The opening mechanism may be any shown earlier, e.g. a movable base orby tipping the container upside down, using the slewing mechanismdescribed earlier.

Discharge container 102 is exemplified by the different embodiments ofFIGS. 8 c-8 e. Each drawing shows a side view of the container and anend view. In each case the contents of the container are moved to adischarge point by at least one screw.

The pollution control container 120 is shown in more detail in FIG. 8 f.It is illustrated with two funnels 126. These collect and direct thematerial falling into this container from above. Below and to the sidesof the funnels 126 are a plurality of exhaust fans 122. Separating eachfan from the inner chamber of the container is a filter 124 for catchingfine dust particles in the exhaust air when the raw material is releasedinto the feed stack from container 10. The undersides of the funnels126, above the exhaust fans and filters act as diverting shrouds forcreating venting spaces for the fans and filters. Below each filtersection is an enclosure 128 to trap dust particles that accumulate andfall off the filter. On the bottom of each enclosure is a valve 129 forperiodic removal of the accumulated dust. This aspect of the inventionprovides for an abatement of dust pollution inherent in this industry.

The fans 122 have a controller to operate them in switchablebi-directional rotations. For normal pollution control during thematerial discharge process, the fans 122 are operated as exhaust fanswith the impellers rotating in the first direction. To clear the dustadhering onto the filter and forcing the dust particle to collect inenclosure 128, the fans are operated as blowers with the impellersrotating in the reverse direction. With this feature, the filter isoperated with higher efficiency. Unnecessary machine breakdown due tofilter choking is avoided. This filter cleaning process may be carriedout periodically using automatic and interlocking control. Additionalvibrating means connected to the filter can also be used to improve thefilter efficiency.

The funnels in the pollution control container may divert the flow ofmaterials to different storage points when a compartmentalised container10″, 10′″ is used to supply different components.

Above the stations 60 and 70 is another pollution control container 80,as shown in FIG. 8 a. As with the pollution control container 120described earlier, there is a plurality of exhaust fans 84 with a filter86 separating the fans from the other chamber of the container intowhich the raw materials are conveyed through chute 50. Above the filterand near the top centre of the container, there is a plurality ofanti-choke cylinders 82. These cylinders are operable to shake off thedirt on the filter to prevent the filters from being clogged up andbecome non-functional.

Depending on the reachable height of the handling facilities at thebatching plant, the feed stack 100 (comprising at least one stockcontainer, a pollution control container and the material supplycontainer) may be mounted directly above the stations 60 and 70. This isillustrated in FIG. 8 b.

A pollution control container 120′ for use with the container slewingapparatus 40 described earlier is illustrated from the side in FIG. 9 aand from the top in FIG. 9 b. This container 120′ is larger thanstandard containers. However it is balanced such that it can stack ontop of them and has twist locks suitably positioned for that purpose. Itis shown stacked on top of stack 100.

As in the other pollution control container described earlier, there isa plurality of fans and filters. Funnel 126′ is used to divert thefalling materials into the container below, such as the stock container104 or other containers in stack 100. This pollution control container120′ has a large frame 132, which is shown in full in FIG. 9 c, andencloses a pair of slewing apparatus 40, mounted on a guide rail 49.This is mounted onto the base 130 of frame 132 by means of twist locks.120′ also has retractable covers 131 at the top. These are closed when asupply container is loaded onto the slewing apparatus for it to beoverturned and the contents discharged. In this manner, the dust createdis contained inside 120′ and the filters trap the dust particles frompolluting the environment. As with the other pollution controlcontainers, the fans' rotation may be reversed periodically to clear thedust particles from clogging up the filters. Additional vibration meansmay also be used to improve the filter efficiency.

FIG. 10 shows yet another embodiment of a material feeding stack. Atranstainer 150 moves along a set of rails and loads/unloads thematerial supply containers 10 onto/from on top of stock containers 104′.This transtainer 150 has a finite working height. In this case, thepollution control features of 120 are integrated into the upper part ofstock container 104′. Below container 104′ is a scaling conveyor 152 forfeeding the right amounts of the different material components to a linkconveyor(s) 153 for discharge into station(s) 70.

Each station 70 is enclosed in a pollution control enclosure 120″. Aswith the other pollution control features, there may be a plurality offans and filters for reducing dust pollution. Additional vibration meansmay also be provided.

In accordance with the requirements of standard freight containers, theyare stacked on top of each other with only the corner castings of onecontainer in contact with those of the other container. This means thatthe interface between containers is open and dust pollution can emanatefrom or enter into the interfacial gaps. Therefore portable seals areprovided to ensure that this pollution control means is effective. FIGS.11 a-11 d illustrate the use of the seals 200, 210. In the case of sealtype 200, these can be inserted from one side once the containers are insitu. Seals 200 are secured in position by means of rotatable locks 201.These locks may be spaced at regular intervals, for example every 0.6 m.In the case of seal 210, these must be placed on a lower containerbefore an upper container is placed.

Containers are usually filled with raw building materials using rathermessy bulk transfer, eg. by means of conveyors, clam shell bucket andcranes; shovel and tractor, etc. During such filling processes, rawmaterials unavoidably fall in between the containers. This is wasteful.Further, when this process is repeated several times it leaves mounds ofmaterial which make placing of the containers awkward and need removing.To minimise accumulation of materials, a cover 140, as shown in FIGS. 12a and 12 b, is used. This clips containers together along their edges,with one cover covering two adjacent lengths, sides or other edges,thereby preventing material falling between them. A different cover 142is used to cover adjacent edges and corner castings. Otherwise thematerial may fall in there too and make it difficult to lock themproperly. Between them covers 140,142 can be used for every adjacentedge. For instance, along the top, several of cover 140 can be usedalong an adjacent length, depending on the lengths of the containers.

FIG. 13 illustrates a system for a container port for containerisedhandling of raw building materials. From a barge or container ship 300,the containers are unloaded by means of a crane or other means (notshown), and unloaded onto prime movers 350 for transfer to the stackingyard by another crane, typically a rubber-tyre gantry crane 400. Withinthe crane operating area, is a concrete production area 500, forinstance the batching plant described earlier. Each component ofconcrete is loaded into the scaling station 60 to determine the amountbefore it is loaded into the station 70. This may include the relevantamount of water if it is required wet immediately. However, a customermay order only the raw building materials. In this case, a containerwith the required type of raw materials is retrieved by the crane,loaded onto a container truck for dispatch to the customer, withoutgoing through the concrete production area.

The containers from the barge or ship can also be known containermixers. In this case, the drums of the container mixers may already becarrying the right amounts of sand and aggregate to produce a commongrade of concrete. These are stacked away for stockpiling or are sent tothe production area 500 where water, cement and other additives arescaled and added to produce concrete. Alternatively, a separate groutingstation 600 is provided just to fill these container mixers.

It is also possible to use the container of this invention for shippingor transferring of other materials or general cargoes that can beunloaded by opening of the base plate or sections of it. This generalcargo includes, but not limited to, any one or more of: goods onpallets; materials in drums or cartons; and machinery. This container,further comprising one or more doors at one or more of the ends and/orsides allow easy loading of goods.

While only a few embodiments of the apparatus and system have beendescribed and illustrated, it is to be understood that many changes,modifications and variations could be made to the present inventionwithout departing from the scope of the invention.

1. A containerized system for transferring bulk materials, and producinga mixture, being shaped and dimensioned in at least length and width tobe handled as a standard freight container comprising: a base, at leasta portion of which is openable for discharging contents of the containertherethrough, wherein said base comprises a plurality of downwardlysloped portions spaced apart from each other forming discharge chutes;at least one compartment, the compartment having at least one lowersection of reducing cross-sectional area, each leading to an opening,and a closure assembly for the opening, for releasing or retaining thecompartment's contents; and a filter means disposed below the closureassembly for allowing fluid to drain through but keeping material insidethe container; wherein the container comprises a plurality of moveablecovers on said discharge chutes operable to close and open the dischargechutes.
 2. The containerized system according to claim 1, wherein the orat least one closure plate is arcuate and is arranged to have asubstantially constant gap between it and its opening, as it is opened.3. A containerized system for transferring bulk materials, and producinga mixture, being shaped and dimensioned in at least length and width tobe handled as a standard freight container comprising: a base, at leasta portion of which is openable for discharging contents of the containertherethrough, wherein said base comprises a plurality of downwardlysloped portions spaced apart from each other forming discharge chutes;at least one compartment, the or each compartment having at least onelower section of reducing cross-sectional area, each leading to anopening, and a closure assembly for the or at least one opening, forreleasing or retaining the compartment's contents; lifting meansattached to the upper sides of the covers to lift them from above;wherein the container comprises a plurality of moveable covers on saiddischarge chutes operable to close and open the discharge chutes.
 4. Thecontainerized system according to claim 3, wherein said lifting meanscomprise flexible means chosen from the group comprising: cable, ropeand chain.
 5. A containerized system for transferring bulk materials,and producing a mixture, being shaped and dimensioned in at least lengthand width to be handled as a standard freight container comprising: abase, at least a portion of which is openable for discharging contentsof the container therethrough, wherein said base comprises a pluralityof downwardly sloped portions spaced apart from each other formingdischarge chutes; at least one compartment, the or each compartmenthaving at least one lower section of reducing cross-sectional area, eachleading to an opening, and a closure assembly for the or at least oneopening, for releasing or retaining the compartment's contents; whereinthe container includes a plurality of triangular-shaped moveable coverson said discharge chutes operable to close and open the dischargechutes, the triangular-shaped moveable covers oriented so a weight ofthe bulk material on the covers induces self-closing of the covers. 6.The containerized system according to claim 5, wherein said covers canbe vertically lifted to open the discharge chutes for discharge.
 7. Thecontainerized system according to claim 6, further comprising anactuator positioned below each of said covers for lifting said covers.8. The containerized system according to claim 6, further comprisingaccess means to allow actuators to access and lift said covers frombelow the container.
 9. The containerized system according to claim 5,wherein the openable portion of the base comprises at least one pair oftwo cooperating halves, with one cooperating edge having an overlap overthe other when said base is closed.
 10. The containerized systemaccording to claim 5, wherein said base further comprises slopingportions along both ends of the container to facilitate the discharge ofthe contents and prevent materials from accumulating at the ends duringdischarge.
 11. The containerized system according to claim 5, beingcompartmentalized, the base of each compartment being openable andclosable independently of each other.
 12. The containerized systemaccording to claim 5, further comprising one or more doors at one ormore of the ends and/or sides.
 13. The containerized system according toclaim 5, wherein at least a portion of the top is slidably or hingablyopenable.
 14. The containerized system according to claim 5, furthercomprising self locking means for securing the openable base portions ina closed position.
 15. The containerized system according to claim 5,further comprising piston means for opening and closing the at least oneopenable portion of said base.
 16. The containerized system according toclaim 5, further comprising seal means around the at least one openableportion of said base, to prevent contamination of the movement mechanismand to minimize wastage of materials.